Wheelchairs are well known in the medical field for giving mobility to disabled persons. Conventionally, wheelchairs include a frame to which wheels are attached, a seat and a back support. The conventional wheelchair has two relatively large rear wheels and two smaller front wheels. The two front wheels are usually pivotally mounted so that the wheelchair can be turned or steered by independent rotation of the two large rear wheels. Typically, the two larger rear wheels are turned by manual manipulation, and for this purpose, an outer concentric rim is normally mounted on the wheel and the concentric rim is turned by the hand to drive and steer the wheelchair. The wheels are generally large enough to allow the disabled person to rotate them by hand and to maneuver the wheelchair to avoid obstacles. Wheelchairs often have handles extending from the rear to allow a second person to push the wheelchair. Wheelchairs do however suffer from a number of significant drawbacks and disadvantages. Their inherent bulk makes it difficult for the wheelchair to enter limited spaces, such as lavatory cubicles. Another commonly encountered problem is that the wheelchair does not allow for easy transfer of the disabled person from the wheelchair to another surface, such as a bed.
U.S. Pat. No. 4,737,997, issued on Apr. 19, 1988, to Lamson discloses a patient transfer device that includes an auxiliary frame, for use with a wheelchair, consisting of a separatable seat and a pivoted frame with a frame adjuster. Disadvantageously, the device may be difficult for a disabled person to maneuver away from the wheelchair and may be unstable since the patient's weight is disposed at the rear of the device. Furthermore, the hinging connection and the frame adjuster only appears to allow for limited movement of the frame. Also, the device appears to be useful for only one size of wheelchair.
Thus there is a need for an auxiliary wheelchair frame that is easy to operate, is adaptable to wheelchairs of different sizes, and which allows a disabled person easy access to areas of limited size.